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Wedge Won't fire without jumper from coil to battery

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arachnid

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I have a 1979 TR7 that I recently put back together, I bought it with the engine in pieces and most of the engine bay items in a box.

I can get it to run if I run a jumper wire from the 12V+ battery to the positive side of the coil. If I remove the wire it will quickly die just like I turned off the key. I'm using Lucus AB14 Electronic Ignition Amplifier. The AB14 puts out 12V to the positive side of the coil

thx for any help
 
I could be totally out to lunch on this one because it has been a long time since I had a TR7, so get a wiring diagram and verify what I am saying. I seem to remember that the power circuit in the "run" position of the ignition switch goes through the oil pressure sensor on the side of the block. If it does not detect sufficient oil pressure it will open the power circuit and kill the engine. You will get the same result if the sensor is faulty. You might want to verify that you are getting voltage through the sensor and up to the coil.
 
trglory said:
I could be totally out to lunch on this one because it has been a long time since I had a TR7, so get a wiring diagram and verify what I am saying. I seem to remember that the power circuit in the "run" position of the ignition switch goes through the oil pressure sensor on the side of the block. If it does not detect sufficient oil pressure it will open the power circuit and kill the engine. You will get the same result if the sensor is faulty. You might want to verify that you are getting voltage through the sensor and up to the coil.
Click to expand...

Thanks for your help. The PO has switched over to a oil pressure gauge so you could be correct, he might have eliminated something. I'll see if I can locate it on the wiring diagram
 
I've heard the ignition switch can be dodgy.
 
I changed the coil in my 1973 TR6 once and use a coil with an internal resistor not knowing that therre was a resistor wire to the coil already . it wouldn't start until I put a coil in with no resistor .
 
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